Photographic roll film spool



Ap 13, 1933- G. OLLENDORFF'. I 1,903,937

PHOTOGRAPHIC ROLL FILM SPOOL Filed Nov is, 1928 I I I i u Z/ /Z/ Z- I In venfor';

Patented A r. 18, 1933 UNITED STATES PATENT OFFICE ennmn'onmnnonn, or wonrmr mum. BITTERFELD, (mam, nssrenon To earn msco conrom'rron, or BmGm'roN, mew YORK, A conronn'rron on NEW YORK PHOTOGBAPHIO SPOOL Applicaticn filed Iovember 13, 1928, Serial No. 81?,171, and in Germany December 8, 1927.

strip.- Its object is to provide a film roll in "which the film strip is always more tensroned than the paper strip, also at the beginning of winding in a photographic camera when loading it. v

Inphotographic roll films the fastening of the light-sensitive strip is usually effecte by attaching its leading end by means of a special adhesive strip or sticker to the protective paper-strip at a certain distance from the leading end of the latter. W1tl1 this arrangement at the beginning of winding 1 n a photographic camera a stronger pull is exerted on the paper than on the strip of film, and in consequence the film, especially in the case of aflanged spool with a small core, does not lie flat in its operative pos1t1on. I found that balance of the stresses exerted on the'paper and on the strip of film can be obtained if a short length" of .the' leading end of the film be passed through a slit or 0 ening in the protective paper strip. an be fastened at its extremity to the outer surface of the latter so that the protective paper strip and the film strip can slide over one another at the opening in the paper strlp.

With this arrangement at the first few ro'- tations of the winding spool a' somewhat greater length of film than of paper is coiled, so that the paper is tensioned more slackl than the film. This difierenceof tension 1s later gradually balanced; the'tension of the paper must, however,-never be greater than viding a suflicient distance between the slit in the protective paper and'the point where the film strip is secured tothe surface of the latter.

The accompanying drawing shows a pho-.

tographic roll film manufactured according to a preferred mode. of carryin out the invention wherein the film strip is secured, to

the protective paper by means of an extenssion of material insensitive-to light.

Fig. 1 is a strip. 7 Fig. 2 is a perspective View of a. roll of film embodying the invention, the leading end of the film strip being unwound from the'roll. a

The attachment of the leading end of the strip of film to the outer surface of the paper can, for'example, be carried out by passlng the leading end 1' of the film 1 through a slit ea 3 formed in theprotective paper strip 2 and securing it position on the outer surface of the paper strip by meansof a sticking strip 5 or other suitable means. Ifdesired the strip of film may also be provided with an extension 4 of material insensitive to light,

perspective view of the film this extension being passed throu h the slit in the protective paper strip and astened to its outer surface. f

" The method of fastening strips of film deg prising a flanged spool with a core, a protec-' tive-pa er str1 provided on its leading end with a s 0t, an a strip of light-sensitive photographic fihn with a tongue-like extension on its leading end, said film lying on the inner surface of the said protective paperstrip and so wound onto the spool with I the latter, ,the. tongue-like extension of said film being passed through said slot in the protective pa r strip and fastened on the outer surface of -t e latter.

' 2. A photogrizlphic roll film cartridge comat prising a flange 'tive paper st'rr provided on its leading and spool with a core, a protecwith a slot, an a strip of light-sensitive photographic film with a strip of material connected totheleading end of said film, said film lying on the inner surface of the saidprotective paper strip and wound onto thespool 'with the latter, the said strip of mate-- rial connected to. said film being passed through said slot in the protective pa r strip and fastened on the outer surface 0 the lat- '3.' A photographic roll cartridge comprising a flange 'l with a core, aprotective paper strip provlded on leading end m0 a slot, and a. strip of light-sensitive photographic film with a strip of material insensitive to light connected to the leading end of said film, said film lying on the inner surface of the said protective paper strip and wound onto the spool with the latter, the said strip of material insensitive to light connecmd to said film being passed through said slot in the protective paper strip and fastened on the 19 outer surface of the latter. i

In testimony whereof, I aflix my si ature.

GERHARD OLLENDO F. 

